291479561 has 4 divisors (see below), whose sum is σ = 293005824. Its totient is φ = 289953300.

The previous prime is 291479557. The next prime is 291479563. The reversal of 291479561 is 165974192.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 291479561 - 2² = 291479557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (291479563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 762845 + ... + 763226.

It is an arithmetic number, because the mean of its divisors is an integer number (73251456).

Almost surely, 2^291479561 is an apocalyptic number.

It is an amenable number.

291479561 is a deficient number, since it is larger than the sum of its proper divisors (1526263).

291479561 is a wasteful number, since it uses less digits than its factorization.

291479561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1526262.

The product of its digits is 136080, while the sum is 44.

The square root of 291479561 is about 17072.7725047808. The cubic root of 291479561 is about 663.0343606666.

The spelling of 291479561 in words is "two hundred ninety-one million, four hundred seventy-nine thousand, five hundred sixty-one".